Primary diffuse large B-Cell lymphoma of the prostate presenting with urinary retention and dyschezia for which rituximab-combined CHOP therapy was effective-a case presentation.

: We report the case of a 66-year-old man with primary diffuse large B-cell lymphoma of the prostate presenting with urinary retention and dyschezia as first manifestation. Although a colostomy was needed due to rectal obstruction, rituximab-combined chemotherapy resulted in complete remission. He underwent stoma closure safely and has remained in complete remission for over 3years. Primary prostatic lymphoma is extremely rare, presenting as 0.1% of newly diagnosed lymphomas, but rituximab-containing chemotherapy seems to be as effective as for nodal lymphoma.